The invention relates to serviceable exhaust aftertreatment devices and to cylindrical bodies configured for coupling.
The invention arose during continuing development efforts relating to serviceable exhaust aftertreatment devices, such as diesel particulate filters (DPF), catalytic elements, mufflers, and the like, including various combinations thereof. An exhaust aftertreatment device requires service at predetermined intervals. In such device, one or more central sections are attached to an inlet section and an outlet section, for flow distribution and mechanical construction, typically application dependent. To service a central section, the inlet section and the outlet section must be removed. Existing serviceable exhaust aftertreatment devices require expensive clamps and sophisticated flanges for joining and sealing mating surfaces, such as 90° flanges. Servicing may include replacement with a new or different element, or may involve a re-usable element wherein soot, ash or contaminant build-up is cleaned from the removed element and then the now-cleaned re-usable element is re-installed. The element may include various types of emissions components.
Design requirements include: serviceability, as noted; structural integrity; leak prevention; cost effective manufacturability; and ease of assembly. A further requirement is low profile mountability. Typical designs in the prior art add 0.5 inch or more to the outer diameter of the device (typically having a diameter in the range of 7 inches to 13 inches), to accommodate the added radial height or dimension of a flange or clamp. This extra 0.5 inch is objectionable in various applications where only severely limited space is available.
The present invention addresses and solves the above noted needs in a particularly simple and effective manner. In one embodiment, the invention requires an increase in outer diameter in the range of 1 to 2% to accommodate the coupled bodies, as opposed to 4 to 7% in the prior art. In one particular embodiment, in an exhaust aftertreatment device having a main body outer diameter in the range of 7 to 13 inches, the present invention requires an increase in outer diameter of only 0.125 inch at the coupling of the bodies. In further aspects, the invention facilitates easy removal and replacement of a central section of the exhaust aftertreatment device.